Answer:
The correct answer is - urine osmolarity.
Explanation:
Urine osmolarity is the test to know the concentration of the substance present in the urine. It helps to know if kidneys working properly or electrolytes properly.
The polydipsia and polyuria are symptoms of the diabetes insipidus that can be diagnosed with the help of the urine osmolarity test. If the urine osmolarity is higher than 700miliOsmol/L it is said that diabetes insipidus present.
Thus, the correct answer is - urine osmolarity.